525 Technical data
Fuels, coolants, lubricants
Engine oils
Engine oils are specifically tested for their 
suitability in our engines and durability for 
our service intervals. Therefore, only use 
approved engine oils and oil filters 
required for vehicles with Maintenance 
System. For a listing of approved engine 
oils and oil filters, refer to the Factory 
Approved Service Products pamphlet 
(USA only), or contact an authorized 
Mercedes-Benz Light Truck Center.Engine oil additives
Air conditioning refrigerant
R-134a (HFC) refrigerant and special PAG 
lubricating oil are used in the air condition-
ing system.
Brake fluid
Only brake fluid approved by 
Mercedes-Benz is recommended. Any 
authorized Mercedes-Benz Light Truck 
Center will provide you with additional 
information.
!Using engine oils and oil filters of 
specification other than those expressly 
required for the Maintenance System, or chang-
ing of oil and oil filter at change intervals longer 
than those called for by the Maintenance System 
will result in engine or emission control system 
damage not covered by the Mercedes-Benz 
Limited Warranty.
Please follow Maintenance System recommen-
dations for scheduled oil changes. Failure to do 
so will result in engine or emission control 
system damage not covered by the 
Mercedes-Benz Limited Warranty.
!Do not blend oil additives with engine oil. 
They may damage the engine.
 Damage or malfunctions resulting from blending 
oil additives are not covered by the 
Mercedes-Benz Limited Warranty.
!Never use R-12 (CFC) or mineral-based 
lubricating oil. Otherwise damage to the system 
will occur.
Warning!G
During vehicle operation, the boiling point of 
the brake fluid is continuously reduced 
through the absorption of moisture from the 
atmosphere. Under extremely strenuous 
operating conditions, this moisture content 
can lead to the formation of bubbles in the 
system, thus reducing the system’s 
efficiency.
Therefore, the brake fluid must be replaced 
regularly. Refer to your vehicle’s 
Maintenance Booklet for replacement inter-
val.